N-of-1 Trials in Hypertension Are Feasible, but Are They Worthwhile?

Excerpt

The use of collective experience to generate expectations for an individual is an example of reference class forecasting.^{1, 2} Most of what has come to be known as evidence-based medicine is in fact an application of this approach, in which average treatment effects, often derived from parallel group randomized controlled trials, are used to make predictions for individual patients. Unfortunately, while the use of average effects has generally proven superior to anecdote, averages do not always apply. The best reference class for an individual is, of course, him or herself. Therefore, the most direct way to estimate the effects of treatment on an individual is to evaluate an individual’s own experience with two or more forms of treatment (where “treatment” may include active treatment, placebo, or routine care). This approach incorporates what have been referred to as single subject experiments, personalized experiments, or N-of-1 trials. …